--- /dev/null
+From f824c65d1fb6a2490b03228e63cc43dae6844f73 Mon Sep 17 00:00:00 2001
+From: Mark Andrews <marka@isc.org>
+Date: Mon, 19 Oct 2015 10:43:58 +1100
+Subject: [PATCH] 4340. [port] Fix LibreSSL compatibility. [RT
+ #40977]
+
+Status: upstream git
+
+Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
+---
+ lib/dns/dst_openssl.h | 2 +-
+ lib/dns/openssl_link.c | 8 ++++----
+ lib/dns/openssldh_link.c | 4 ++--
+ lib/dns/openssldsa_link.c | 4 ++--
+ lib/dns/opensslrsa_link.c | 2 +-
+
+diff --git a/lib/dns/dst_openssl.h b/lib/dns/dst_openssl.h
+index dd67405..12f8bfc 100644
+--- a/lib/dns/dst_openssl.h
++++ b/lib/dns/dst_openssl.h
+@@ -36,7 +36,7 @@
+ #define USE_ENGINE 1
+ #endif
+
+-#if OPENSSL_VERSION_NUMBER < 0x10100000L
++#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
+ /*
+ * These are new in OpenSSL 1.1.0. BN_GENCB _cb needs to be declared in
+ * the function like this before the BN_GENCB_new call:
+diff --git a/lib/dns/openssl_link.c b/lib/dns/openssl_link.c
+index 8683bee..6a52b31 100644
+--- a/lib/dns/openssl_link.c
++++ b/lib/dns/openssl_link.c
+@@ -88,7 +88,7 @@ entropy_getpseudo(unsigned char *buf, int num) {
+ return (result == ISC_R_SUCCESS ? 1 : -1);
+ }
+
+-#if OPENSSL_VERSION_NUMBER < 0x10100000L
++#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
+ static void
+ entropy_add(const void *buf, int num, double entropy) {
+ /*
+@@ -121,7 +121,7 @@ lock_callback(int mode, int type, const char *file, int line) {
+ UNLOCK(&locks[type]);
+ }
+
+-#if OPENSSL_VERSION_NUMBER < 0x10100000L
++#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
+ static unsigned long
+ id_callback(void) {
+ return ((unsigned long)isc_thread_self());
+@@ -187,7 +187,7 @@ dst__openssl_init(const char *engine) {
+ if (result != ISC_R_SUCCESS)
+ goto cleanup_mutexalloc;
+ CRYPTO_set_locking_callback(lock_callback);
+-#if OPENSSL_VERSION_NUMBER < 0x10100000L
++#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
+ CRYPTO_set_id_callback(id_callback);
+ #endif
+
+@@ -287,7 +287,7 @@ dst__openssl_destroy(void) {
+ CRYPTO_cleanup_all_ex_data();
+ #endif
+ ERR_clear_error();
+-#if OPENSSL_VERSION_NUMBER < 0x10100000L
++#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
+ ERR_remove_state(0);
+ #endif
+ ERR_free_strings();
+diff --git a/lib/dns/openssldh_link.c b/lib/dns/openssldh_link.c
+index 9f42219..67fbf69 100644
+--- a/lib/dns/openssldh_link.c
++++ b/lib/dns/openssldh_link.c
+@@ -173,7 +173,7 @@ openssldh_generate(dst_key_t *key, int generator, void (*callback)(int)) {
+ DH *dh = NULL;
+ #if OPENSSL_VERSION_NUMBER > 0x00908000L
+ BN_GENCB *cb;
+-#if OPENSSL_VERSION_NUMBER < 0x10100000L
++#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
+ BN_GENCB _cb;
+ #endif
+ union {
+@@ -210,7 +210,7 @@ openssldh_generate(dst_key_t *key, int generator, void (*callback)(int)) {
+ if (dh == NULL)
+ return (dst__openssl_toresult(ISC_R_NOMEMORY));
+ cb = BN_GENCB_new();
+-#if OPENSSL_VERSION_NUMBER >= 0x10100000L
++#if OPENSSL_VERSION_NUMBER >= 0x10100000L && !defined(LIBRESSL_VERSION_NUMBER)
+ if (cb == NULL) {
+ DH_free(dh);
+ return (dst__openssl_toresult(ISC_R_NOMEMORY));
+diff --git a/lib/dns/openssldsa_link.c b/lib/dns/openssldsa_link.c
+index 963e2f5..d47b265 100644
+--- a/lib/dns/openssldsa_link.c
++++ b/lib/dns/openssldsa_link.c
+@@ -359,7 +359,7 @@ openssldsa_generate(dst_key_t *key, int unused, void (*callback)(int)) {
+ isc_result_t result;
+ #if OPENSSL_VERSION_NUMBER > 0x00908000L
+ BN_GENCB *cb;
+-#if OPENSSL_VERSION_NUMBER < 0x10100000L
++#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
+ BN_GENCB _cb;
+ #endif
+ union {
+@@ -383,7 +383,7 @@ openssldsa_generate(dst_key_t *key, int unused, void (*callback)(int)) {
+ if (dsa == NULL)
+ return (dst__openssl_toresult(DST_R_OPENSSLFAILURE));
+ cb = BN_GENCB_new();
+-#if OPENSSL_VERSION_NUMBER >= 0x10100000L
++#if OPENSSL_VERSION_NUMBER >= 0x10100000L && !defined(LIBRESSL_VERSION_NUMBER)
+ if (cb == NULL) {
+ DSA_free(dsa);
+ return (dst__openssl_toresult(DST_R_OPENSSLFAILURE));
+diff --git a/lib/dns/opensslrsa_link.c b/lib/dns/opensslrsa_link.c
+index 94aced2..d799be0 100644
+--- a/lib/dns/opensslrsa_link.c
++++ b/lib/dns/opensslrsa_link.c
+@@ -771,7 +771,7 @@ opensslrsa_generate(dst_key_t *key, int exp, void (*callback)(int)) {
+ } u;
+ RSA *rsa = RSA_new();
+ BIGNUM *e = BN_new();
+-#if OPENSSL_VERSION_NUMBER < 0x10100000L
++#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
+ BN_GENCB _cb;
+ #endif
+ BN_GENCB *cb = BN_GENCB_new();
+--
+2.4.10
+